diff --git a/server/models/index.js b/server/models/index.js
index b4bee75..232fcb3 100644
--- a/server/models/index.js
+++ b/server/models/index.js
@@ -5,86 +5,98 @@ if (process.env.NODE_ENV !== 'test') {
   require('dotenv').config();
 }
 
-// Configure database based on environment
-let sequelize;
-if (process.env.NODE_ENV === 'test') {
-  // Use SQLite file database for testing to allow sharing between modules
-  sequelize = new Sequelize({
-    dialect: 'sqlite',
-    storage: './test.db',
-    logging: false
-  });
+// Check if models are already initialized (for tests)
+if (global.__TEST_MODELS__) {
+  module.exports = global.__TEST_MODELS__;
 } else {
-  // Use PostgreSQL for production/development
-  sequelize = new Sequelize(
-    process.env.DB_NAME || 'drone_detection',
-    process.env.DB_USER || 'postgres',
-    process.env.DB_PASSWORD || 'password',
-    {
-      host: process.env.DB_HOST || 'localhost',
-      port: process.env.DB_PORT || 5432,
-      dialect: 'postgres',
-      logging: process.env.NODE_ENV === 'development' ? console.log : false,
-      pool: {
-        max: 5,
-        min: 0,
-        acquire: 30000,
-        idle: 10000
+  // Configure database based on environment
+  let sequelize;
+  if (process.env.NODE_ENV === 'test') {
+    // Use SQLite in-memory database for testing
+    sequelize = new Sequelize({
+      dialect: 'sqlite',
+      storage: ':memory:',
+      logging: false
+    });
+  } else {
+    // Use PostgreSQL for production/development
+    sequelize = new Sequelize(
+      process.env.DB_NAME || 'drone_detection',
+      process.env.DB_USER || 'postgres',
+      process.env.DB_PASSWORD || 'password',
+      {
+        host: process.env.DB_HOST || 'localhost',
+        port: process.env.DB_PORT || 5432,
+        dialect: 'postgres',
+        logging: process.env.NODE_ENV === 'development' ? console.log : false,
+        pool: {
+          max: 5,
+          min: 0,
+          acquire: 30000,
+          idle: 10000
+        }
       }
-    }
-  );
+    );
+  }
+
+  // Import models
+  const Device = require('./Device')(sequelize);
+  const DroneDetection = require('./DroneDetection')(sequelize);
+  const Heartbeat = require('./Heartbeat')(sequelize);
+  const User = require('./User')(sequelize);
+  const AlertRule = require('./AlertRule')(sequelize);
+  const AlertLog = require('./AlertLog')(sequelize);
+  const Tenant = require('./Tenant')(sequelize);
+  const ManagementUser = require('./ManagementUser')(sequelize);
+
+  // Define associations
+  Device.hasMany(DroneDetection, { foreignKey: 'device_id', as: 'detections' });
+  DroneDetection.belongsTo(Device, { foreignKey: 'device_id', as: 'device' });
+
+  Device.hasMany(Heartbeat, { foreignKey: 'device_id', as: 'heartbeats' });
+  Heartbeat.belongsTo(Device, { foreignKey: 'device_id', as: 'device' });
+
+  User.hasMany(AlertRule, { foreignKey: 'user_id', as: 'alertRules' });
+  AlertRule.belongsTo(User, { foreignKey: 'user_id', as: 'user' });
+
+  AlertRule.hasMany(AlertLog, { foreignKey: 'alert_rule_id', as: 'logs' });
+  AlertLog.belongsTo(AlertRule, { foreignKey: 'alert_rule_id', as: 'rule' });
+
+  DroneDetection.hasMany(AlertLog, { foreignKey: 'detection_id', as: 'alerts' });
+  AlertLog.belongsTo(DroneDetection, { foreignKey: 'detection_id', as: 'detection' });
+
+  // Tenant associations
+  Tenant.hasMany(User, { foreignKey: 'tenant_id', as: 'users' });
+  User.belongsTo(Tenant, { foreignKey: 'tenant_id', as: 'tenant' });
+
+  Tenant.hasMany(Device, { foreignKey: 'tenant_id', as: 'devices' });
+  Device.belongsTo(Tenant, { foreignKey: 'tenant_id', as: 'tenant' });
+
+  // Auto-sync database in test mode
+  if (process.env.NODE_ENV === 'test') {
+    sequelize.sync({ force: true }).then(() => {
+      console.log('🗄️  Test database tables created');
+    }).catch(error => {
+      console.error('❌ Test database sync failed:', error);
+    });
+  }
+
+  const models = {
+    sequelize,
+    Device,
+    DroneDetection,
+    Heartbeat,
+    User,
+    AlertRule,
+    AlertLog,
+    Tenant,
+    ManagementUser
+  };
+
+  // Store models globally for tests
+  if (process.env.NODE_ENV === 'test') {
+    global.__TEST_MODELS__ = models;
+  }
+
+  module.exports = models;
 }
-
-// Import models
-const Device = require('./Device')(sequelize);
-const DroneDetection = require('./DroneDetection')(sequelize);
-const Heartbeat = require('./Heartbeat')(sequelize);
-const User = require('./User')(sequelize);
-const AlertRule = require('./AlertRule')(sequelize);
-const AlertLog = require('./AlertLog')(sequelize);
-const Tenant = require('./Tenant')(sequelize);
-const ManagementUser = require('./ManagementUser')(sequelize);
-
-// Define associations
-Device.hasMany(DroneDetection, { foreignKey: 'device_id', as: 'detections' });
-DroneDetection.belongsTo(Device, { foreignKey: 'device_id', as: 'device' });
-
-Device.hasMany(Heartbeat, { foreignKey: 'device_id', as: 'heartbeats' });
-Heartbeat.belongsTo(Device, { foreignKey: 'device_id', as: 'device' });
-
-User.hasMany(AlertRule, { foreignKey: 'user_id', as: 'alertRules' });
-AlertRule.belongsTo(User, { foreignKey: 'user_id', as: 'user' });
-
-AlertRule.hasMany(AlertLog, { foreignKey: 'alert_rule_id', as: 'logs' });
-AlertLog.belongsTo(AlertRule, { foreignKey: 'alert_rule_id', as: 'rule' });
-
-DroneDetection.hasMany(AlertLog, { foreignKey: 'detection_id', as: 'alerts' });
-AlertLog.belongsTo(DroneDetection, { foreignKey: 'detection_id', as: 'detection' });
-
-// Tenant associations
-Tenant.hasMany(User, { foreignKey: 'tenant_id', as: 'users' });
-User.belongsTo(Tenant, { foreignKey: 'tenant_id', as: 'tenant' });
-
-Tenant.hasMany(Device, { foreignKey: 'tenant_id', as: 'devices' });
-Device.belongsTo(Tenant, { foreignKey: 'tenant_id', as: 'tenant' });
-
-// Auto-sync database in test mode
-if (process.env.NODE_ENV === 'test') {
-  sequelize.sync({ force: true }).then(() => {
-    console.log('🗄️  Test database tables created');
-  }).catch(error => {
-    console.error('❌ Test database sync failed:', error);
-  });
-}
-
-module.exports = {
-  sequelize,
-  Device,
-  DroneDetection,
-  Heartbeat,
-  User,
-  AlertRule,
-  AlertLog,
-  Tenant,
-  ManagementUser
-};
diff --git a/server/tests/setup.js b/server/tests/setup.js
index 8399ba2..9511cb3 100644
--- a/server/tests/setup.js
+++ b/server/tests/setup.js
@@ -1,5 +1,21 @@
 // IMPORTANT: Set environment variables FIRST, before any other imports
-process.env.NODE_ENV = 'test';
+proces  // Return test context
+  models = {
+    sequelize,
+    Device,
+    DroneDetection,
+    Heartbeat,
+    User,
+    AlertRule,
+    AlertLog,
+    Tenant,
+    ManagementUser
+  };
+
+  // Store models globally so routes can access them
+  global.__TEST_MODELS__ = models;
+
+  return { sequelize, models };est';
 process.env.JWT_SECRET = 'test-jwt-secret-key-for-testing-only';
 process.env.DATABASE_URL = ':memory:';
 process.env.DB_DIALECT = 'sqlite';
@@ -20,7 +36,7 @@ afterEach(() => {
 // Test database configuration
 const testDatabase = {
   dialect: 'sqlite',
-  storage: './test.db', // Use same file database as models/index.js
+  storage: ':memory:', // In-memory database for fast tests
   logging: false, // Disable SQL logging in tests
   sync: { force: true } // Always recreate tables for tests
 };
@@ -32,6 +48,9 @@ let models;
  * Setup test environment before all tests
  */
 async function setupTestEnvironment() {
+  // Clear any existing global models
+  delete global.__TEST_MODELS__;
+  
   // Create test database connection
   sequelize = new Sequelize(testDatabase);